JPS595165Y2 - Diesel engine intake throttle device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an intake throttle valve control device for controlling an intake throttle valve operated during idling of a diesel engine.

Recently, easel passenger cars have been put into practice due to their economic efficiency, but the vibration and noise generated from the easel engine installed in them has become a major problem.

Particularly during idling, torque fluctuations within one cycle, ie, angular velocity fluctuations, are large, and this is one of the factors that increases vibration.

In view of the above-mentioned points, this proposal is designed to throttle the intake air during idling operation, and to control the opening degree of the throttle opening based on the engine's working fluid pressure such as oil pressure, engine water temperature, intake negative pressure, etc. It is an object of the present invention to provide a throttle valve control device.

An example of this will be described below with reference to the drawings.

Reference numeral 1 denotes an intake throttle valve integrally attached to a shaft 2. The shaft 2 is rotatably supported by a case 3, and an arm 4 for rotating the shaft 2 is provided at one end thereof.

A case 3 of the intake throttle valve 1 is disposed in the middle of an intake passage 5 of an easel engine.

6 is a negative pressure responsive actuator, and diaphragm 7
The negative pressure chamber 8 is connected to a vacuum pump 11 via a suitable pipe 10, and has a return spring 1 inside which presses the diaphragm 7.
2,12a are provided.

On the other hand, the atmospheric chamber 9 is provided with a hole 13 through which it communicates with the atmosphere, and a rod 14 is disposed with one end fixed to the diaphragm 7 and the other end extending outward. The outer end of the intake throttle valve 14 is connected directly or via a suitable rod or link to an arm 4 integral with the shaft of the intake throttle valve 1.

Reference numeral 15 denotes a three-way solenoid valve disposed in the middle of the pipe 10, which includes a negative pressure inlet portion 15a, an outlet portion 15b, and an atmosphere (open) port 15.
C, and the outlet portion 15b is selectively connected (disconnected) to the inlet portion 15a and the atmosphere port 15C by a built-in control valve (not shown).

16 is a pressure detection switch, for example, an oil pressure detection switch that detects the oil pressure of the engine oil gear and operates the electromagnetic valve 15.
In this embodiment, when the oil pressure is low such as when the engine is idling, the contact is opened, and when the engine speed increases and the oil pressure exceeds a set value, the contact is closed and the solenoid valve 15 is activated. It is set to operate.

17 is a circuit that connects the detection switch 16 to the electromagnetic valve 15, and 18 is a battery.

Reference numeral 24 denotes a water temperature sensing valve disposed between the solenoid valve 15 and the actuator 6, and the water temperature sensing element portion 25 is installed so as to face the water jacket W of the cylinder body B of the engine. It opens and closes an internal passage (not explicitly shown) depending on the operation.

26 is a negative pressure control valve, vacuum pump 11 etc. solenoid valve 1
A negative pressure chamber 28 partitioned by a diaphragm 27 is connected to a pipe 2 on the downstream side 5a of the intake throttle valve 1.
9, and the diaphragm 27 is actuated by detecting the intake negative pressure on the downstream side 5a.

31 is a return spring.

Reference numeral 29 denotes a conical valve portion that is attached to the diaphragm 27 and operates together with the diaphragm 27 to control the amount of atmospheric air introduced into the pipe 10 from the atmospheric chamber 30.

Since the proposed device is configured as described above, for example,
During normal idling operation of the engine, the oil pressure in the oil gear is low, and the detection switch 16 does not close until the set pressure is reached, and the internal passage of the water temperature detection valve 24 is also open. The spring 12 returns to the negative pressure chamber 8 of the actuator 6 due to its action.
．． Since the diaphragm 7 is pulled to the left in the figure against the force 12H, the rod 14 is also pulled in the same direction.

Accordingly, the intake throttle valve 1 is rotated counterclockwise in the figure via the arm 4 to throttle the intake air passing through the intake passage 5.

In this way, the intake air volume is reduced, thereby reducing the engine's angular velocity fluctuation and vibration acceleration in the rolling direction, and the engine vibration during idling.

The effect of reducing noise can be obtained.

Furthermore, along with the reduction in engine vibration and noise as described above, vehicle body vibration and shift lever vibration are also reduced.

Next, if the intake negative pressure on the downstream side 5a of the intake throttle valve 1 does not become larger than necessary, the valve portion 29 of the negative pressure control valve 26 will resist the return spring 31 according to the magnitude of the negative pressure. Since it is lifted upward in the figure, the amount of atmospheric air introduced increases and the negative pressure is weakened, so that the opening degree of the intake throttle valve 1 is maintained almost constant.

Therefore, the intake air is not excessively throttled by the intake throttle valve 1.

In addition, even in the same idling operation, at cold start, etc., the internal passage of the water temperature sensing valve 24 is closed until the water temperature sensing valve 24 reaches the set temperature regardless of the operation of the solenoid valve 15, so the actuator 6 does not operate and the intake throttle valve 1 remains open, so there is no adverse effect on starting the engine.

Furthermore, regardless of whether the engine is at room temperature or cold start, when the engine is in an operating state other than idling, the oil pressure increases and exceeds the set pressure value, causing the detection switch 16 to close.

Therefore, the electromagnetic valve 15 works, and the negative pressure outlet 15b is disconnected from the negative pressure inlet 15a and communicated with the atmospheric air port 15C, so the actuator 6 stops operating and the intake throttle valve 1 returns to the open position. do.

Therefore, the intake throttle in the intake passage 5 is released.

Therefore, during normal driving of the vehicle, performance deterioration such as a decrease in engine output does not occur.

Note that the opening/closing operation of the oil pressure detection switch 16 may be reversed from that in this embodiment, but in that case, it goes without saying that the function of the solenoid valve 15 will also be opposite to that in this embodiment.

Further, in this embodiment, an example of oil pressure is shown as the working fluid pressure of the engine, but it is natural that substantially the same operation and effect can be obtained even if the water pressure of the engine cooling water is used.

[Brief explanation of drawings]

The figure is a schematic system diagram showing an embodiment of the present invention. 1; Intake throttle valve, 5; Intake path, 6; Actuator,
11; Vacuum pump; 15; Solenoid valve; 16; Oil pressure detection switch; 24; Water temperature detection valve; 26; Negative pressure control valve.

Claims (1)

[Scope of utility model registration request] An intake throttle valve that is operated in the closing direction by a negative pressure-responsive actuator that operates by introducing negative pressure from a vacuum pump into the intake passage is provided, and an intake throttle valve that is operated in the closing direction by a negative pressure response type actuator that is operated by introducing negative pressure from a vacuum pump is installed in the pipe that connects the vacuum pump and the actuator. A solenoid valve that detects the set pressure of the fluid and operates; a water temperature sensing valve that detects the set temperature of the engine cooling water and closes; and a negative intake pressure downstream of the intake throttle valve that detects the magnitude of the negative pressure. An intake throttle valve control device for a diesel engine, characterized in that it is equipped with a negative pressure control valve that introduces outside air in proportion to the intake air.